Here’s what could point to more upside for oil

Crude oil has already bounced back by 30 percent over the past month. But according to Richard Ross of Evercore ISI, currency market moves are predicting more upside for the battered commodity.

Over the past week, oil-exposed currencies such as the Canadian dollar, the Norwegian krone and the Australian dollar have surged in value against the U.S. dollar. And since these currencies tend to be correlated with crude, Ross extrapolates that oil has more upside.

Crude-exposed currencies "are really firming here, and they have been firming over the past month or so along with crude oil itself, and I think that holds bullish implications," Ross said.

Looking at the Canadian currency in particular, Ross predicts that "the Canadian dollar continues to firm against the U.S. dollar, and this should be supportive of crude."

Even the crumbling Russian ruble has had a great run over the past month, Ross points out.

"Earlier this year, the ruble was staring into the abyss," he said in a Thursday "Trading Nation" segment. "Strength in the Russian ruble, once again, has a positive read-through for crude oil."

However, not everyone buys the thesis.

Referring to the commodity currencies, Boris Schlossberg of BK Asset Management said that "they're kind of reactive. It's hard to make that case completely."

In other words, crude is driving currencies like the Canadian dollar, and not the other way around.

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